Engine cooling system



Dec. 2, 1958 E. w. RoHRBAcHER ET AL 2,862,483

ENGINE COOLING SYSTEM 2 Sheets-Sheet 1 Filed 00's. 4. 1954 E. w.ROHRBACHER ET AL 2,862,483

ENGIN COOLING SYSTEM Y De'c. 2, 1958 United States Patent C)l ENGINEcooLlNG SYSTEM Application october 4, 1954, serial No. 460,205 13claims. (AC1. 12s-41.73)

This invention relates to cooling systems for internal combustionengines and has particular relation to an improved cooling systemespecially applicable for V-type, 8cylinder internal combustion enginesfor automotive and other uses. Y

It has been the practice heretofore to construct cooling systems forinternal combustionengines by providing cooling cavities in the headsand blocks of engines and then supplying cooling liquid to andexhausting cooling liquid from these cavities. To provide a good coolingsystem it has been the practice to make these cavities as large aspossible within the space and cost limitations applicable, it havingbeen assumed that the availability of large quantities of'cooling liquidadjacent the parts to be cooled would provide the best cooling systempossible. However, it now appears that in these systems thecoolingliquid supplied generally circulated between the cavity inlets andoutlets by the shortest possible path or by the path oifering the leastrestriction to the flow of cooling liquid. Since the cavities were largethe cooling liquid had a tendency to stratify in other parts of thecavities and to circulate only by thermosyphon circulation caused by theadjacent heated parts of the engine or by entrainment in the stream ofcooling liquid owing between the inlet and the outlet for the cavities.Since the most highly heated parts of the engine were usually not in theshortest path between the inlet and the outlet or the path where therewas less restriction to the flow of cooling liquid-between the inlet andthe outlet, the parts requiring the greatest cooling often were providedwith the least effective means for cooling. Also, the provision oflargecooling cavities tended to enclose parts that did not requirecooling. .This caused the heat rejection to the cooling liquid to -beexcessive and required excessive and unnecessarily expensive heatradiating means for the engine.

It is proposed to limit the size of the cooling liquid cavities in aninternal combustion engine and to provide means for directing thecirculation of cooling liquid within the cavities so that substantiallyall of the cooling liquid in the cavities will be compelled to followdefinite circulation paths within the cavities and over the parts of theengine that especially require cooling by the cooling liquidA suppliedto the engine. The reduction in the size of the cooling cavitiesparticularly in the heads of the engine tends to exclude from thecavities various heated parts of the engine that do not require cooling.Since this decreases the amount of heat that must be absorbed by thecooling liquid circulated throughout the engine, it is possible toemploy a smaller and much less expensive radiator for the engine. Inthese cooling cavities of reduced size it is proposed to provide vmeansfor creating a definite and continuous circulation throughout thecooling cavities of the engine so that the cooling liquid will bepositively circulated over all the heated parts ofl the engine thatrequire cooling. Hence the stratification of liquid in various parts ofthe cooling cavities where .cooling is required will be greatly reducedif not entirely 2,862,483 Patented Dec. 2, 1958 eliminated. In parts ofthe engine where space limitations might require the construction ofnarrow passages and in parts through which the circulation of coolingliquid would be diicult it is proposed to employ cooling by conductivitythrough the metallic parts of the engine to places where bettercirculation of cooling liquid can be obtained. This also reduces therejection of heat to the cooling liquid of the engine and thereforedecreases the size of the radiator due to the factv that these heatconducting parts also radiate heat to various objects adjacent theengine and are cooled by the air surrounding ice the engine so that theamount of heat that must be con` will insure against stratification ofthe cooling liquid in places where circulation is required.

In the drawing:

Figure 1 is a fragmentary end elevational view of an engine havingvarious parts thereof broken away and shown in cross-section to betterillustrate the features of the cooling system employed in the'engine.

Figure 2 is a plan view of the engine disclosed by Figure l.

Figure 3 is a cross-sectional view taken substantially in the plane ofline 3-3 on Figure 1 and having various parts of the structure brokenaway and illustrated in cross-section to better illustrate the featuresof the cooling system embraced in the heads of the engine.

lFigure 4 is a diagrammatical illustration of the operation of thecooling liquid distribution nozzle disclosed by Figure 5 and showing howthe nozzle distributes the cooling liquidthroughout the lower part ofthe inside cavities in each bank of cylinders of the block.

Figure 5 is a cross-sectional view taken through the front wall of theengine and illustrating a cooling liquid distribution nozzle employed inthe cooling system embracing the invention.

Figure 6 is anend View of one ofthe distribution nozzles as illustratedby Figures 4 and 5.

The engine 10 embodying the invention comprising an engine block 11 inwhich parallel rows vof obliquely disposed'cylinders 12 are formed.Pistons 13 are adapted to reciprocate in the cylinders 12 in response tothe operation of connecting rods 14 which are rotated and reciprocatedby the crankshaft 16 of the engine. The cylinders 12 are formed bycylinder walls 17 and are surrounded by cooling cavities 18 which areformed within the outer or cooling liquid jacket walls 19 of the block11. The cavities 18 extend between and at the ends of the rows ofcylinders 12 and throughout the length of the rows of cylinders 12 andon opposite sides thereof. The cylinders 12 are closed by heads 21secured tothe block 11 by bolts 22. The heads 21 provide ring chambers23 for each of the cylinders 12 and in which spark plugs 24 and inletand exhaust valves 26 and 27 respectively are provided. Theringrchambers 23 and the ports for the inlet and exhaust valvesv26 and27 are formed in inner walls 28 of the heads 21 which close the ends ofthe cylinders 12 and directly engage the outer end surfaces of eachcylinder bank of the block 11. The heads 21 contain cooling liquidcavities 29` which are provided by cooling liquid cavity or jacket walls31 which enclose a limited amount of space upwardly of the inner walls28 and adjacent the ring chambers 23. Inlet passages 31 and the exhaustpassages 32 lead inwardly and outwardly respectively through thecavities 29 and from the inlet valves 26 and the exhaust valves 27. Theexhaust passages extend outwardly to branch passages 25 leading toexhaust manifolds 33 and the inlet passages 31 extend inwardly to branchpassages 34 leading to one or the other of the maindistribution passages3 6 of the 4inlet manifold 37 of'the engine 10.' Itispioposed toconstruct the walls 38u forming the exhaus'tpassages 32 in such manneras to extend the exhaustspa'ssages 32 upwardly andoutwardly 'fromv thecylinders'` 12 of thev engine vwith as little curvature as is possiblein the exhaust passages`32. Then itlis proposed to construct theouterlside walls 39 of the heads 21 to intersect the outer ends of thepassages 32 substantially normally and to extend upwardly from the outersides of theheads 21 substantially in-parallel 'relation to the verticalyplane of the engine. This will provide' exhaust passages of minimumlength which will be adequately cooled adjacent the exhaust valve stemguidesv 41 and the ports in'which the exhaust valves 27 are seated. -Itis only for the purpose of lcooling the exhaust valvestetn guides and'the exhaust ports that it is necessary `te cool any `of the wallsinwhich the exhaust passages'32 are formed. It is considered preferable toprovide a separate exhaust ypassage 32 for each of the exhaust valves 27of the engine so that the walls 33 may extend vdirectly to the sidewalls 39' and therefore be of minimum length.

It is also proposed to form the ,inner walls 42 of the heads 21 toextend substantially in' parallel relation to the axes of the cylinders12 and to intersect the walls forming the inlet passages 31substantially normally. It has been the practice heretofore to disposethe walls 42 outwardly toward the inlet manifold' and to secure theinlet manifold to the inner walls of the heads. This has been done toincrease the size of the cooling cavities in the heads as may be seenfrom the fact that the walls of the inlet passages are cooled by theincomingcharge and do not require cooling by the cooling liquid of theengine. In the present instance it is proposed to move the inner walls42 inwardly to enclose within the heads only the space immediately abovethe cooling cavities 18 on the inside of the cylinders 12 and to reduceto a minimum the cooling liquid cavity 29 within the heads 21. The outerwalls 44 of the heads 21 may be disposed substantially in parallelrelation to the inner walls 28 and in ,spaced relation to the wallsforming the outlet passages 31 except at the outer edges thereof wherethey maybe turned *outwardly slightly in normal relation to the stemsfor the valves 26 and 27. It will be noted that the walls 39, 42 and 44of the heads are positioned to include as little as possible of thewalls forming the inlet and exhaust passages extending through the headto reduce the cavities 29 to a minimum size.

Y A pump 46 may be bolted or otherwise secured at 47 i to thefront oftheblock 11 for the purpose of supplying cooling liquid, preferably water,to the cooling cavities 18 and 29 in the block and heads of the engine.Any suitable pump may be employed although in the present instance it isconsidered preferable to employ a pump with an impeller 48 having vanes49 which are substantially radially disposed at the outer extremitiesthereof and curved inwardly at the inner extremities thereof to lead thevanes 49 as in Figure 1 the impeller 4S rotates in a clockwisedirection. It is customary to drive the impeller 48 by employing a shaft51 on which the fan of the engine is mounted. This necessitates securingthe casing 52 of the pump to the front wall of the engine near the upperpart of the block 11. Outwardly of the impeller 48 it is consideredpreferable to provide an enlarged distribution chamber 53 whichcompletely surrounds the impeller 48 and tapers in opposite directionsVtoward outlet passages 54 leading from the pump casing. The outletpassages S4 at each end of the distribution chamber 53 are adaptedtofcommunicate with inlet openings formed in the front wall 56 of theblock 11 near the upper extremities of the c avities v43 thatextendthe-length of Atheblock 11 and inside-the cylinders 12. Nozzles 57 areadapted to be pressed in the openings in the wall 56 to extend inwardlyof the cavities 43 at one side of the walls 17 of the cylinders 12.Orifces 58 are provided in the rounded outer ends 59 of the nozzlesV 57.The orices 58 are not as Wide as the nozzles 57 and are elongated inplanes between and parallel to the yinner surfaces of the inner sidewalls of the block 11 and the adjacent surfaces of the walls 17 of thecylinders 12. The orifices 58 are also formed in the roundedends 59 ofthe nozzles 57 so that the upper extremities of the orifices intersecttheside walls of the nozzles toward the extreme ends of the Vnozzles-and beyond the place where the rounding of the ends cornmences. Thisresults in the ends of the nozzles adjacent the upper ends of theorifices 58 forming curved and downwardly directed deflection means 59adjacent the extremities of the nozzles 57. The lower ends of theoriiices 58 are adapted to extend beyond the rounded ends 59 and toterminate toward the opposite ends of the nozzles 57. Since theoriiice's58 are not as large as the outlet passages 54 nor the parts of thenozzles 57 leading to the oriiices 58 it will be apparent that thevelocity of the cooling liquid owing through the orifices 58 will beincreased by the orices 58 to discharge the cooling liquid into theupper parts of the inner cooling cavities 43 in high velocity streams asis indicated by the Vflow lines in Figure 4. The upper parts 59 of therounded ends of the nozzles will cause these streams to be dischargeddownwardly in the inner cavities 43 and the narrow and elongated form ofthe orifices 58 will cause these streams to be directed toward thebottom of the cavities 43 and substantially throughout the greater part`of the length thereof. At'the lower extremities of the cavities 43 itwill be apparent that the cooling liquid in fthe streams discharged bythe nozzles 58 will be dellected between the lcylinders 12 and to thelower extremities of the elongated cavities 61 on the outer sides of thecylinders 12. Therefore, the pump 46 will supply cooling liquid to thelower extremities of the cooling cavities 18 in the block 11 andsubstantially through@ out the length of the block 11. l

As the ycooling liquid in the cavities 18 is displaced upwardly by thecontinuous supply of cooling Vliquid through the nozzles 57 the coolingliquid will absorb heat from the cylinder `walls 17 for cooling thecylinders and the pist-ons v1? reciprocating therein. It will also'beapparent that the temperature of the cooling liquid will increase as itapproaches the-upper extremities of the cylinders and that there wil-lbe no by-pass through the cooling cavities 18 vwhere'theliquidsupplied'by the pump 46 may-take the shortest path of movement betweenthe pump outlets .54 and the upper extremities of the cyl-l inders 12. v

It is proposed to transfer the coolingliquid from Vthe block cavities 18to the head cavities `29 principally through the pairs of mainsupplypassages indicated at 62 and 63. The supply passages 62 and 63 maybeformed through the lower walls of the heads and the upper walls of theblock in parallel relation to the axes of the cylinders 12.v vIt isproposed to locate the passages 62 on the outer sides of the heads 29and immediately within the outer side walls 39 which are not disposed inparallel relationto'the axes of the cylinders 12 lbut in substantiallyparallel .relation to the central vertical plane of the engine l10. Itisproposed to locate one of the main supply passages 62 between each lpairof the cylinders 12. In each pair of the cylinders 12 it is proposed toarrange the inlet valves 26 on the adjacent sides of the cylinders andthe exhaust valves 27 on the opposite sides of the cylinders with thevalves extending substantially across diameters of the cylinders andsubstantially aligned throughout the length of each head.- It istherefore proposedv to arrange the main supply passages 62 adjacent theouter side walls 39 and between pairs vof the cylinders 12in which theinlet valves 26 are disposedonadjacent sides ofthe cylinders. The supplypassages 62 therefore will be located a consider- .passages 63 are theinlet passages 31 able distancefrom the exhaust passages 32 which extenddirectly outwardly from the exhaust valves 27. The main supply passages63 are to be located directly across the heads 21 from the passages 62'and in close proximity to inwardly directed parts 64 of the inner sidewalls 42 of the heads 21. The passages 63 are therefore located betweenpairs of the cylinders 12 and on the inlet valve sides of the cylinders12. Immediately above the supply by which combustible mixtures aresupplied to the( cylinders 12. Since the inlet valves 26 are on adjacentsides of pairs of the cylinders 12 it will be apparent that the inletpassages 31 for each pair of the cylinders 12 may be brought togetherclosely enough so that a common dividing wall may be provided betweenadjacent passages 31 for the pairs of the cylinders 12. It is proposedto form the inlet passages 31 of. substantially rectangularcrosssectional configuration between the inlet valves 26 and the innerextremities .of the heads 21. Under such circumstances the lower wallsofl each pair of inlet passages 31 will be substantially flat. Since theinlet passages 31 are directed inwardly of the heads 21.and toward thebranch passages in the inlet manifold 37 it is possible to position thecommon lower wall for each pair of the inlet passages 31 in spacedrelation to the inner walls 28 ot' the heads 21 with the innerextremities of the lower walls merging with the inner walls 28 aroundthe seats for the inlet valves 26 and the outer extremities thereofclosely approaching the inner walls 28 adjacent the inner side walls 42.Under such 'circumstances it will be apparent that the common lowerwalls of the pairs of inlet passages for the pairs of cylinders in eachhead will provide circulation deectionbaies 66 immediately above each ofthe main supplypassages 63. It will be apparent that when streams ofwater discharged'into the heads 21`through the mainsupply passages 62and 63, the streams from the supply passages 62 will move upwardly inthe cavities 29 and along the outer side v walls 39 of the heads whichare disposed obliquely and are directed inwardly with respect to thestreams. However, the streams of liquid supplied by the passages 63 willflow inwardly of the cavities 29 and directly against the circulationbatlies 66 provided by the lower walls of adjacent pairs of the inletpassages 31. These streams of liquid discharged by the supply passages62 and 63 willcause a circulation of liquid in the lower parts of thecavities 29 in planes extending transversely of the engine heads andsubstantially throughout the entire length of the engine heads. Thiswill be apparent when it is considered that the streams -of liquiddischarged by the main supply passages 63 are prevented from owingupwardly in the cavities 29 `by the batlles 66, are prevented fromflowing outwardly by the inwardly extending parts 64 of the outer sidewalls 42, are prevented from'flowing directly across the cavities 29 bythe inlet valves 26 and therefore must divide to form two streams whichflow outwardly of the baffles 66 and toward the exhaust valves 27 onopposite sides of each pair of the cylinders 12. It will be noted thateach cylinder of the engine has five of the bolts 22 for securing theheads 21 tothe block 11. The bolts 22 are arranged inv three rowsthroughout the length of the engine with the middle row of boltsextending through bolt columns 67 and the inner row extending throughbolt columns 68. It will be noted that one of the bolt columns 67 ispositioned between each pair of the cylinders 12 and immediatelyadjacent the supply passages 63. These bolt columnswill cause thestreams of liquid supplied by the passages 63to divide immediatelyadjacent the passages 63 to ow around the columns 67 and the placeswhere the lower walls of the pairs of inlet passages 31 merge with theinner walls 28. Also, it will be noted that a pair of the` bolt columns68 are located on each side of the supply passages 63 and Ain a positionto deect the divided streams toward the exhaust valves 27. It willtherefore be apparent that the divided streams 6 of liquid supplied bythe supply passages 63. will flow outwardly from beneath the baiiie 67and toward the ends of the exhaust passages 32 which communicate withthe exhaust valves 27 and which extend v across the heads 21 in adirection opposite that in which the inlet passages 31 extend. It willbe further apparent that the streams of liquid directed upwardly by thesupply passages 62 and deilected inwardly by the side walls 39 willentrain liquid in the parts of the cavities 29 between the exhaustpassages 32. The liquid so entrained will result in low fluid pressureareas beyond the inner ends of the inlet passages 31 and adjacent theouterends of the exhaust passages 32. Since iow pressure areas willcause the divided streams of liquid supplied by the passages 63 to flowaround the ends of the walls 38 in which the exhaust passages 32 areformed and to cool the walls 38 and particularly 'the parts of the walls38 adjacent the exhaust ports formed inthe lower walls 28. .It will benoted that the baiile 66 will direct the divided streams outwardly andimmediately-adjacent the lower walls 28 and directly toward the exhaustvalve seats. After the divided streams of liquid flow around the ends ofthe exhaust passage walls 38 the liquid will move upwardly along thewalls 39 as the liquid is entrained in the streams .of .liquiddischarged by the main supply passages 62.

This movement of liquid around the inlet valves and V'across the headsadjacent the lower walls 28 and upwardly adjacent the vside walls 39will result in a circulation of liquid transversely of the heads andabout an axis extending throughout the length of the heads and nor.-

mally intersecting theparallel transverse planes through the axes of thecylinders 12. This will be apparent when itis considered that at theupper extremities of the walls 3,9 the liquid will engage the upperwalls 44 and particularly the outer extreme parts rof the upper walls 44which are v constructed in such a way as to be normal to the axes of thestems of the valves 26 and 27. These parts of the upper walls44 willdeflect the liquid downwardly and inwardly and toward the upper walls ofthe pairs of inlet passages 31' and toward the space between and onopposite sides of the pairs of inlet passages 31. The liquid that isdirected between and on opposite sides of the pairs of inlet passages31.will be entrained in the divided streams of liquid flowingoutwardlyfrom beneath the innerextremities of the baie 66. The' liquidengaging the upper walls of the pairs of inlet passages 31 will bedeflected in opposite directions to be entrained in the liquid movingdownwardly between the pairs of inlet passages. It will, therefore, beapparent that instead of the liquid introduced into the heads merelyilowing upwardly in the heads and outwardly through the path vof leastresistance the liquid will be compelled to circulate inv the heads andover the walls of the tiring chambers 23 and across the parts of thewallsin which the exhaust 'ports are formed, these being thefparts ofthe heads that need' the greatest cooling.

It will be noted that the outer side walls 39 merge with the inner walls28' of the heads at the large ends of the ring chambers 23 which areformed in the inner walls 28 of the'heads. The walls 39 also merge withbosses 71 through which pairs of the bolts 22 located on opposite sidesof the spark plugs for each cylinder extend. The bosses 71 and themerging walls 39 and 28 at the larger 'ends of the firing chambers 23form relatively thick wall sections 72 which vprovide relatively lowresistance paths for conductivity of heat from the larger ends of thefiring chambers 23 and from around the spark plugs 24. The wall sections72 are surrounded bythe cavities 29 in the heads 21V and the cavities 18in the block 11. These thick wall sections indicated at 72 and thebosses 71 therefore will rapidly conduct heat to the cavities 29 and 18and to parts of they cavities 29 and 18 where relatively wide surfaceareas at they edges of thepsections 72 are exposed to the cooling liquidin the cavities 29 and 18. In order to increase the conductivity betweenthe sections 72 and the walls of the block 19 so that the heat from thesections 72 may. be more rapidly absorbed by the liquid in the cavities18 in the block it is proposed to employ metallic head gaskets 73 whichwill conduct heat better than asbestos or other gaskets which may beemployed.

It willv be noted that the upper parts of the cavities 29 in the heads21 are the inner parts of the cavi-ties and that these .inner parts arerelatively remote from the parts in which liquid is circulated acrossthe exhaust valve ports and the tiring chambers of the engines. Coolingliquid therefore may tend to stratify in the upper parts of the cavities29, particularly above the walls forming the inlet passages 31andbetween the upper parts of the side walls forming the passages 31. Thestratified `cooling liquid in such parts of the cavities 29 therefore isfree to move lengthwise of the heads where at the front ends of theheads outlet passages 74 are formed. The outlet passages 74 are adaptedto communicate with a passage 76- formed in manifold 77 eX- tendingacross the heads 21 at the front of the engine. The outlet 78 from themanifold 77 may be connected to the radiator of the engine which byreason of the improved cooling system previously described may begreatly reduced in heat radiating surface and cost. The heads 21 may bemade reversible if this is desired and Vin such instance the outletpassages 74 will be provided at each end of the heads 21. With suchpassages 74 provided at each end of the heads the passages at the rearof the heads may be closed by walls 76 extending from the connectingwall 77 in which the inlet and cooling liquid manifolds 37 and 77respectively may be formed.

At places in the cavities 29 which are somewhat remote from the mainsupply passages 62 and 63 it may befound desirable to provide secondarysupply passages indicated at 75. These may be employed to supplyadditional cooling liquid -from the cavities in -the block to thecavities in the head and to prevent stratiiication of liquid in theremote parts vof the cavities of the heads. Also, one of these auxiliarypassages which is indicated at 78 may be positioned aboutthe middle ofthe cavities 29 and adjacent the exhaust cross-over passage 79; The.passage 79 -leads -fromone of the exhaust passages 32 toward the middleof the engine and communicates with the exhaust heating passage 81 whichis formed in the connecting wall 77 and which is employed for heatingthe inlet mani- Afold37.

We claim:

15. A cooling system for an 4internal combustion engine comprising anengine block having a row of cylinders formed therein and cooling liquidcavities surrounding said cylinders throughout the length of said block,a head forsaid cylinders secured to said block and having cooling liquidcavities formed therein, a pair of inlet passages formed in said headand extending through said cavities in said head from inlet portsleadingto an adjacent pair of said cylinders and terminating in a sidewall ofsaid head, said inlet ports being disposed on adjacent sides of. saidpair of cylindersl and said pair of inlet passages being formed fromsaidports to said side walls to include a commonl lower wall extendinglaterally in said head in spaced relation to the lower wall of saidhead, a pair of spaced exhaust ypassages formed in said head andextending'from exhaust ports formed on opposite sides of said inletports and terminating in an opposite side walll of said` head, a coolingliquid supply passage extending between said cavities in said head andblock andformed in the lower wall of said head and adjacent said oneside wall of said head and between the opposite edges of said commonlower wall of said inlet passages and being positioned to discharge astream of cooling liquid into said head and against said common lowerwall of said inlet passages, saidvstream of cooling liquid beingdirected to engage said common lower wall ofsaid inlet passages and tobe deflected by said lower wall and said one side wall to form twostreams of cooling liquid flowing toward said opposite'wall andoutwardly from beneath saidl common lower wall and against the `-innerends of said exhaust ,passages adjacent saidvexhaust. ports, and meansfor exhausting said cooling. liquid from said head.

2. A cooling system for an internal combustion engine having an engineblock and a pair of cylinders formed therein and comprising a headsecured to said block and upon said cylinders and having cooling cavitymeans formed therein, a pair of inlet and exhaust valves disposed insaid head and in opposed relation to the ends of each of said cylinders,said inlet valves being disposed on adjacent sides of adjacent cylindersand said exhaust valves being disposed on the opposite sides of saidadjacent cylinders, a pair ofexhaust passages formed in said head andextending across said cooling cavity means from said exhaust valves insaidl adjacent cylinders to one side wall of said adjacent head, meansdisposed between said cylinders and onthe side of said adjacentcylinders opposite said exhaust passages for directing a column ofcooling liquidvupwardly within said cooling cavity means, a battleformed in said head in opposed relation to said column and extendingfrom the opposite side wall of said head toward said inlet valves and inspaced relation to the inner wall'of said head, said bailie being formedto terminate in said-inner wall and adjacent said inlet valves andbetween said exhaust valves and said exhaust passages to provideoppositely disposed outlets from between said bai-lle and said innerwall, said baiie being positioned to direct said uid suppliedby saidcolumn of fluid from beneath said baille around said inlet valves andupon Vthe inner extremities of said exhaust passages.

3. A cooling system for an-internal combustion engine as defined byclaim 2 and.in which another means is provided in said inner wall ofsaid head for discharging a column of cooling liquid upwardly into saidcooling ,cavity means, said other means being located adjacent saidopposite wall of said head and between said cylinders and between saidpair of exhaust passages.

4. A method of cooling a cylinder of an internal cornbustion enginehaving a cavity in the head of the cylinder for cooling liquid forcooling the cylinder and in which said head isformed to provide inletand exhaust passages communicating with said cylinder and extendingacross said cavity and comprising, moving cooling liquid in said cavityfrom the outlet toward the inlet end of said inletv passage, thenmovingsaid liquid along the lower wall of said head and toward and intocontact with the inlet end of said exhaust passage and along saidexhaust passage toward theV outlet'- end of said exhaust passage, andthereafter moving said liquid away from said exhaust passage and toapart of said cavity adjacent the inlet end of said inlet passage. 4 5. Amethod of cooling a cylinder of an internal cornbustion engine havingacavity in the Ihead of the cylinder for `cooling liquid for cooling thecylinder and in which said head is formed toy provide an exhaust passagecornrmunicating with Said cylinder and extending across said cavity, andcomprising, moving cooling liquid in said cavity towardsand'into contactwith the inletrend of said exhaust passage and along said exhaustpassage toward the outlet end of saidexhaust passage, and thereaftermoving said liquid away from said outlet end of said exhaust passage andtoward said inlet end of said exhaust passage.

6. A method of cooling a cylinder of an internal combustion enginehaving a cavity in the head yof the cylinder for cooling liquid forcooling the cylinder and in which said head is formed to provide anyexhaust passage extending across said cavity, and comprising, supplyingcooling liquid to said cavity in a continuous stream during theoperation of said engine, directing said stream at the inlet end of saidexhaust passage, continuing the movement of said stream towardl theoutlet end of said exhaust passage, reversing the movement of saidstream by .moving said liquid away from said outlet end of said exhaustpassage and toward said inlet end of said exhaust passage, dividing saidstream adjacent the inlet end of said exhaust passage and exhaustingsome of said liquid from said cavity, and thereafter directing theremaining part of said stream toward the inlet end of said exhaustpassage.

7. A method of cooling a cylinder of an internal combustion enginehaving a cavity in the head of the cylinder for cooling liquid forcooling the cylinder and in which said head is formed to provide anexhaust passage communicating with said cylinder and extending acrosssaid cavity, and comprising, supplying cooling liquid to said cavity ina pair of continuous streams during the operation of said engine,directing one of said streams toward the inlet end of said exhaustpassage and transversely of said cylinder and toward the outlet end ofsaid exhaust passage, and directing the other of said streamstransversely of said exhaust passage and adjacent the outlet end of saidexhaust passage.

8. A method of cooling the cylinders of an internal combustion engine inwhich the cylinders are arranged in a row and having cavity means in thehead means for said row of cylinders for cooling liquid for cooling saidcylinders and in which said head means is formed to provide oppositelydirected inlet and exhaust passages communicating with said cylindersand with the inlet and outlet ends thereof terminating in opposite sidewalls of said head means and comprising, supplying and exhaustingcooling liquid to and from said cavity means in said head means, androtating said liquid in said cavity means about an axis extendinglongitudinally of said head means and transversely to the axes of saidcylinders and in a direction to move along the inner wall of said headmeans from the inlet side to the exhaust side of said head means. y

9. A method of cooling the cylinders of an internal combustion engine inwhich the cylinders are arranged in a row and having a cavity in thehead for said row of cylinders for cooling liquid for cooling saidcylinders and in which said head is formed to provide oppositelydirected inlet and exhaust passages communicating with said cylindersand with the inlet and outlet ends thereof terminating in opposite sidewalls of said head, and cornprising, continuously supplying andexhausting cooling liquid to and from said cavity in said head,directing said cooling liquid supplied to said head against said inletpassages on one side of said head, and directing said cooling liquidsupplied to said head between said exhaust passages on the opposite sideof said head.

10. A method of cooling the cylinders of an internal combustion enginein which the cylinders are arranged in a row and having a cavity in thehead for said row of cylinders for cooling liquid for cooling saidcylinders and in which said head is formed to provide oppositelydirected inlet and exhaust passages extending across said cavity andcommunicating with said cylinders and with the inlet and outlet endsthereof terminating in opposite side walls of said head and with thelower walls of said passages spaced from the lower wall of said head,and comprising, supplying and exhausting cooling liquid to and from saidv10 cavity in said head, directing said cooling liquid supplied to saidhead against said lower walls o said inlet passages on one side of saidhead and directing said cooling liquid supplied to said head betweensaid exhaust passages on the opposite side of said head.

ll. A cooling system for an internal combustion engine having cylindersarranged in a r-ow and having a cavity in the head for said row ofcylinders for cooling liquid for ycooling said cylinders and in whichsaid head is formed to provide oppositely directed inlet and exhaustpassages extending through said cavity and communicating with saidcylinders and with the inlet and outlet ends thereof terminating inopposite side walls of said head and with the lower walls of saidpassages spaced from the lower wall of said head, and comprising meansfor directing cooling liquid against the lower Walls of said inletpassages and toward the inlet ends of said exhaust passages, and meansfor supplying cooling liquid to and for exhausting cooling liquid fromsaid cavity.

12. A cooling system for an internal combustion engine having cylindersarranged in a row and having a cavity in the head for said row ofcylinders for cooling liquid for cooling said cylinders and in whichsaid head is formed to provide oppositely directed inlet and exhaustpassages extending through said cavity and communicating with saidcylinders and with the inlet and outlet ends thereof terminating inopposite side walls of said head and with the lower walls of saidpassages spaced from the lower wall of said head, and comprising, meansfor directing a stream of cooling liquid against the walls of said inletpassages and toward the inlet ends of said exhaust passages and alongthe walls of said exhaust passages toward the outlet ends of saidexhaust passages, and means for supplying cooling liquid to and forexhausting cooling liquid from said cavity.

13. An internal combustion engine having a row of cylinders and a headfor said row of cylinders, said head being formed to provide a coolingliquid cavity therein for cooling said cylinders, a pair of inletpassages having a common lower wall spaced from the lower wall of saidhead and entering said head through a side wall of said head andcommunicating with adjacent sides of a pair of said cylinders, a pair ofoutlet passages formed in said head and communicating with oppositesides of said pair of cylinders and having the outlet ends thereofterminating in an opposite side wall of said head, means for dischargingcooling liquid into said head and against said common lower wall of saidinlet passages, and means for discharging cooling liquid into said headand into the space between said exhaust passages.

References Cited in the file of this patent UNITED STATES PATENTS2,175,448 Schlagintweit Oct. 10, 1939 2,182,990 Kishline Dec. 12, 19392,186,080 Sheldrick Jan. 9, 1940 2,339,972 Anderson et al Ian. 25, 19442,533,442 Falcon Dec. 12, 1950

